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Einstellvorschriften / Adjustment Procedures
Adjustments
1. CD-Section
Measuring instruments/equipment: Oscilloscope, test CD 5A (part no. 72008-376.00)
Note: Do not turn the variable resistor (laser power adjustment). The laser current is pre-set at the factory.
Adjustment
Preparations
1. Focus Offset
Connect the oscilloscope to testpoint TP1, ground to
TP2.
a.) load the test CD
b.) close the CD door
c.) CD function: Play
2. Tracking
Connect the oscilloscope to testpoint TP3, ground to
EF Balance
TP2.
a.) load the test CD
b.) close the CD door
c.) CD function: Play
VR2
TP1
VR3
TP2
IC1
J36
R88
R74
CN11
CN4
CN3
TC3
TC2
T204
L204
TC1
TC4
L203
SW201
FM ANT.
T203
TP
1
1 - 11
Adjustment Processs
Adjust VR2 to obtain a clear eye pattern as shown
in the diagram.
VOLT/DIV: 0.5V TIME/DIV: 1ms
Adjust VR3 so that the graph is symmetrical to the
0-line (Vref).
V1=V2
VOLT/DIV: 20mV TIME/DIV: 1ms
VR301
T301
TP
4
TP3
CN301
SW301-
IC301
CD PCB
TP
L206
2
3
VR201
13
17
IC202
1
Tuner PCB
T201
T202
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K-RCD 500
Einstellvorschriften / Adjustment Procedures
2. Cassette Deck
Measuring instruments/equipment: Frequency counter, AF-voltmeter, wow and flutter meter,
Fe test cassette 449 (part no. 35079-019.00), torque test cassette 456 (part no. 35079-014.00).
Adjustment
1. Tape speed
Connect the frequency counter to the headphone socket.
Insert the test cassette 449,
play 3150Hz.
2. Take-up torque
Insert the torque test cassette 456.
on Start
Function: Playback-Start.
3. Wow and flutter
Connect the wow and flutter meter to the headphone
max. 1.4V
>1V
pp
± 0.1V pp
socket.
Insert test cassette 449,
play 3150Hz.
4. Head gap angle
Connect the AF-voltmeter to the headphone socket.
(Azimuth)
Insert test cassette 449,
V1
play 8kHz.
0
(Vref)
V2
5. Bias frequency
Connect the frequency counter to TP
Insert a recordable cassette.
Function: Record-Start.
6. Bias voltage
Connect the AF-voltmeter via a 1:1000 capacitive voltage
divider to TP
4
(R/P head).
Insert a recordable cassette.
Function: Record-Start
3. Tuner
Measuring instruments: Standard signal/sweep signal generator, oscilloscope, frequency counter.
Adjustment
1. AM
Couple in a sweep signal of 465kHz at L206 (ferrite
IF
aerial) via a loop aerial.
Oscilloscope to TP 2 (IC202, Pin17).
Function switch: AM
2. AM (MW)
MW 526.5kHz, MW 1606.5kHz
Oscillator
Couple in a standard signal frequency at L206 (ferrite
Audio PCB
aerial) via a loop aerial. (f
Oscilloscope to the headphone socket.
3. AM (MW)
MW 600kHz, MW 1400kHz
Aerial bandpass
Couple in a standard signal frequency at L206 (ferrite
aerial) via a loop aerial. (f
Oscilloscope to the headphone socket.
4. FM
Feed in a 10.7MHz sweep signal to TP 1 (FM-ant.).
IF
Oscilloscope to output TP 2 (IC202, Pin17).
Function switch: FM
5. FM
FM 87.5MHz, FM 108MHz
Oscillator
Couple in the standard signal frequency to TP 1 (FM-
= 1kHz, ∆f = 22.5kHz).
ant. f
mod
Oscilloscope to the headphone socket.
6. FM
FM 90MHz, FM 106MHz
Aerial bandpass
Couple in the standard signal frequency to TP 1 (FM-
= 1kHz, ∆f = 22.5kHz).
ant. f
mod
Oscilloscope to the headphone socket.
7. FM
Feed in a standard signal of 98MHz, unmodulated to
MPX
TP 1 (FM-ant.).
(Stereo)
Frequency counter to TP 3 (IC202, Pin13).
Band switch: FM-Stereo
1 - 12
Preparations
Adjustment Process
With adjustment control (in the cass.-motor) set the
±
frequency to 3150Hz
0.1%.
Tape tension on:
Playback-Start = 35 - 65g-cm
Fast Forward = 50 - 120g-cm
Fast Rewind = 50 - 120g-cm
Deviation < 0.25% (aurally compensated). Playback
measuring time ≥ 30 seconds.
With the head adjustment screw 1
set the left and right channel to
maximum level.
The levels of the two channels must
not differ by more than 3dB.
4
(R/P head).
The oscillator frequency should be 60kHz
Adjust with T301.
The bias voltage is approx. 15mV (measured with a
1:1000 capacitive voltage divider).
Adjust with VR301.
Preparations
Adjustment Process
Adjust T202 to obtain maximum.
At f
(526.5kHz) adjust to maximum with T203.
u
At f
(1606.5kHz) adjust to maximum with TC4.
o
= 1kHz 30%).
Repeat this adjustment.
mod
At 600kHz adjust to maximum with L206.
At 1400kHz adjust to maximum with TC2.
= 1kHz 30%).
Repeat this adjustment.
mod
With T204 and T201 adjust to maximum.
Repeat this adjustment.
At f
(87.5MHz) adjust to maximum with L204.
u
At f
(108MHz) adjust to maximum with TC3.
o
Repeat this adjustment.
At 90MHz adjust to maximum with L203.
At 106MHz adjust to maximum with TC1.
Repeat this adjustment.
Set the frequency to 38kHz ± 100Hz with VR201.
K-RCD 500
1
±
10 kHz.
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